August s



UNITED STATES TTTCJE.

AUGUST S. HELD, OF FREEPORT, ILLINOIS, ASSIGNOR TO THE STOVERMANUFACTURING-COMPANY, OF SAME PLACE.

SPRING-HINGE.

SPECIFICATION forming part of Letters Patent No. 515,334, dated February27, 1894.

Application filed March 23, 1893. Serial No. 467,286- (No model.)

To aZZ whom it ntay concern:

Be it known that 1, AUGUST S. HELD, acitizen of the United States ofAmerica, residing at Freeport, in the county of Stephenson and State ofIllinois, have invented certain new and usefullmprovements inSpring-Hinges, of which the following is a specification.

My invention relates to improvements in spring hinges of that class inwhich two leaves of suitable form provided with pivotally connected earsare combined with a sheet metal spring placed between the ears andhaving its ends fastened to the leaves. In hinges of this kind thespring has usually been bent into the form of an incomplete cylinderopen at the side next the leaves and having each of its ends fastened tothe corresponding leaf in such a way that the ends were nearest togetherand the cylinder was of least diameter when the hinge was in its closedposition, the ends being drawn apart and the cylinder being expanded bythe opening of the hinge. It is evident that a spring thus constructedand operated must work at a great disadvantage, since at every openingof the hinge, it must be bent in a reverse direction to that by which itwas given its cylindrical form, and that the constant tendency must beto destroy the elas ticity of the spring and thus impair its value. Thisis not only a theoretical conclusion, but it is borne out by the resultsof actual and repeated tests and may be taken as a settled fact. Inorder to overcome this difliculty I have simply changed the general formof my sheet metal spring by crossing its ends and making it a completelyclosed cylinder, the relation of the ends of the spring to the twoleaves being reversed as compared with the hinge having the ordinaryconstruction above referred to. The result of this change ofconstruction is that the opening of-the hinge increases the distance towhich the ends are crossed and contracts the diameter of the cylindermade up of the spring, the fiexure of the spring as the hinge is openbeing thus in the same direction as that applied to the spring informing it into a cylinder.

The invention is fully described and explained in this specification andshown in the accompanying drawings, in which Figure l is a frontelevation of a complete hinge in working position. Fig. 2 is ahorizontal section through the line 22, Fig. 1, the view being downward.Fig. 3 is a side elevation of a hinge, the view being in the directionindicated by the arrow in Fig. 1. Fig. 4 is a plan of the blank fromwhich the spring is formed; and Fig. 5 is a plan of a modified form ofblank.

In Figs. 1 to 4, A, A are two leaves of suitable form provided at theirends with ears pivoted together in the usual manner to form hingejoints. The inner edges of the leaves are formed with loops, at, a,respectively, adapted to receive and retain the hooked ends of a springof suitable form and in the space between the ears is placed acylindrical sheet metal spring, B, form ed on one of its edges with asingle central leg, I), and on its opposite edge with two symmetricallyplaced legs, I), b, separated by a space slightly wider than the leg,I). The legs, b, b, b, are crossed as shown in the drawings and theirends are formed into books, the hooks on the outer legs, I), I), beingin engagement with the loops, a, on the leaf, A, and thehook on thecentral leg, I), being in engagement with the loop, a, on the leaf, A.It is evident that the opening of the hinge from the closed positionshown in Fig. 2 must not only separate the hooks, b, b, but mustincrease the distance to which they are crossed and contract thecylinder into which the body of the spring is formed. In this operationthe spring is bent in the same direction as that required in forming itoriginally, and there is no reason why a spring properly tempered shouldnot stand the strain of such use for an indefinite period.

The outer edges of the legs, I), b, may evidently be straight linescontinuous with the ends of the blank from which the spring is formed,but I prefer to form them with recesses, 1*, Fig. 4, the re-entrantangles of these recesses being obtuse as shown, or being curved lines.It is also preferable to make the recesses, r, r, on opposite side ofthe central leg, b, in substantially the same form as the shallowerrecesses, T and I prefer also to make the opening, r between the legs,I), b, in substantially the form shown in Fig. 4.

Fig. 5 shows a blank in which one of the edges is formed with threelegs", I), b, b, and the opposite edge with twd'legs', b, 17', adaptedtopass through spaces between the legs, I), b, 1). Whatever may be theform of the blank or the number of legs, it is desirable that the legsbe so symmetrically placed that the spring may be balanced when inworking position.

The hinge shown in the drawings is" what is known as a hold-back hinge,that is, a hinge in which the force of the spring tends equally to closeor open the hingeffrom a certain neutral position between its limit ofmotion, this neutral position being knownas the dead point and beingreached when the hinge pivot and the points of connection of the springwith the two leaves are all in the same plane. I do not, however, intendto limitthe use of this form ofspring to a holdback hinge, since it maybe so applied to a hinge as to tend to close it from any position whichits leaves may assume. As shown in the drawings, the spring, B, is verynearly in the form' of a perfect cylinder and in the following claims,itis spoken of as approximately cylindrical. I do" not, however, intendto limit my invention" in this respect to this specific crosssection,-though the cylindrical form is probably preferable to any other.

Having now described and explained my .inventiomwha't I claim as new,and desire to I secure by Letters Patent, is

1. In a spring hinge, the combination with two leaves of suitable form,of a sheet metal spring formed into approximately cylindrical form andhaving its ends crossed and attached to the leaves respectively, wherebythe opening of the hinge from its closed position increases the distanceto which the 1 ends are crossed and decreases the diameter of thecylinder; substantially as shown and described.

, 2. In a spring hinge, the combination with two leaves of suitable formhaving ears pivf oted together to form knuckle joints, of the sheetmetal spring bent into approximately cylindrical form, the oppositeedges of the spring being formed with legs crossing each other andfastened to the leaves of the hinge respectively; substantiallyas shownand described.

3. In a spring hinge the combination with two leaves suitably pivotedtogether,of a sheet metal spring bent into approximately cylindricalform and having on one of its edges AUGUST s'. HELD.

Witnesses.

L. HUGHES, I W. H. J. STRATTON.

